Preheat oven to 400 F and brush a 7x11” baking dish with butter (you can also use a 9" round pie dish for a taller pie)
Heat oil and butter in a nonstick pan over medium heat. Add the onion and sauté until translucent, then add garlic and chicken stock cubes, and sauté for another min
Add the flour and milk, and cook while stirring for a few seconds. Add all the seasoning and cook until the mixture starts to bubble
Turn off heat and add the shredded chicken, veggies and cheese. Taste and adjust seasoning as needed. You can also adjust the consistency: if you want it to be more runny, add more milk (remember, it will become thicker when baked)
If adding a bottom layer of crust, add that to your pie dish first. If not, skip that and add the filling to the prepared pish dish
Cut the pie crust into 2" squares and arrange them on top of the filling. Make sure to poke some holes or leave a few small gaps so steam can escape
Make the egg wash by mixing the egg yolk and milk, and generously brush the pie crust on top with the egg wash
Bake for 30-40 min until the pie looks nicely golden and crispy. If it starts to brown too much, cover with aluminum foil
Serve while it’s hot and enjoy!
